The present invention relates to a new and distinct cultivar of Vitex agnus-castus hereinafter referred to as ‘V0502-33’.
Pedigree and history: ‘V0502-33’ originated from a cross of Vitex agnus-castus ‘Shoal Creek’ (unpatented) and Vitex rotundifolia (unpatented) which were caged together with honeybees as pollinators in the summer of 2005 under the direction of David Knauft. Seeds were collected from the female parent ‘Shoal Creek’, and may have resulted from self-pollination or crosses with Vitex rotundifolia. These seeds were sown, and the seedlings were grown in a cultivated area in the spring and summer of 2006. Nineteen plants were selected based on desirable horticultural qualities, and were propagated in Watkinsville, Ga. via stem cuttings in August 2006. In April 2007, the resulting propagated plants in the form of liners were transplanted into containers or the field at a location in Watkinsville, Ga. Based on container and field performance, a plant identified as ‘V0502-33’ was selected. This ‘V0502-33’ selection is most likely the result of a self-pollination of ‘Shoal Creek’; it is fertile and has no apparent characteristics of V. rotundifolia. Stem cuttings were made from this ‘V0502-33’ plant, and distributed to Carol Robacker, who took over this breeding program in 2009. Plants reproduced from these stem cuttings were planted in a replicated field plot (three reps, randomized block design) in Griffin, Ga. (USDA zone 8a) in the fall of 2009.
‘V0502-33’ plants have been evaluated for four years at this site. Height and width data have been collected annually. Cold damage was assessed each spring. Mean panicle length and number of panicles per compound panicle were counted each summer. First bloom and re-bloom dates were noted each year. Data was collected on leaf yellowing, leaf drop, thinning, and leaf spot in July, August and September of each year. In addition, two asexually propagated (by cuttings) replicates were also planted in Blairsville, Ga., in spring 2011, to assess performance in this colder environment (USDA zone 7a). In March of 2011, rooted liners of this new plant were shipped to Bonsall, Calif. for evaluation.
Vitex agnus-castus is a deciduous shrub or small tree used in landscapes. This drought tolerant plant may be grown in cold hardiness zones 6 through 9. During cold winters in zone 6, it may die back to the ground, but will likely re-grow from the roots and produce a flowering shrub during the following summer, as flower buds are formed on new growth. Late spring freezes in zone 7 may also cause cold damage and dieback, but the plants recover and bloom during the summer. The new plant is intended to be distributed for landscape use in the U.S. and perhaps in other countries.